>>12736708A minor note I would like to add is that the reason why I used the word "sin" instead of "crime" in the OP is because I think feigning love for someone for the sake manipulating them is something that a person should feel remorse over, instead of expecting that it's something others will hold them accountable for.
I agree that a person should never be expected to have to play along somebody else's fantasies of them being a couple, especially not if there was no explicit mutual confession of love at any point in time, but what I had in mind was the opposite (people who let themselves be called somebody else's "girlfriend" or "husband" without feeling any affection towards them).
I acknowledge the fact that there is no true, well-established foundation for the whole premise behind this thread besides deceit being wrong, but I would like to at least assume that it's possible to say that telling lies, or acting as if lies told by others were true, and taking advantage of others by the means of them is not correct.